Fig. 2.

Characterization of BTVM1 and BTVM14 mutant viruses. (A) The total titer at different time points postinfection for either mutant or WT viruses in complementary BSR/NS3 cells (left panel) or normal BSR cells (right panel) was determined, expressed as PFU/ml, and plotted on a logarithmic scale. (B) The expression of NS3 was assessed in cell lysates from mammalian BSR cells at 48 h postinfection with mutant virus BTVM1 (lane 2) or BTVM14 (lane 3); cell lysates from mock-infected cells (lane 4) or WT-infected cells (lane 1) were included. Lane M, molecular mass standard in kDa. Western blotting was performed using an antibody against BTV NS3. (C) Genomic dsRNA from BSR cells infected with WT virus (lane 1) or mutant virus BTVM1 (lane 2) or BTVM14 (lane 3) was purified and analyzed on a nondenaturing polyacrylamide gel.